Abstract Wave with Particle System
Method 1 - Dupliverts

You should use a mesh such as a cube or a simple Icosphere for your particle, this will allow you to properly shade the particles like any other mesh


Select the particle mesh, in my case an Icosphere
Select the ocean
parent the particle to the ocean, Ctrl P
Select the ocean
In mesh panel, set duplication type to verts




http://www.pasteall.org/pic/show.php?id=67612

Method 2 - Particle System


Make sure your particle system is one the bottom of the modifier stack.


In the particle system enable Use Modifier Stack


If you want to use another mesh as the particles you need to select the particle system and under the render tab, Select Object as your render type. Then you can choose you object.